1. Department Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
2. Showa Denko K.K., 1-13-9, Shibadaimon, Minato, Tokyo 105-0012, Japan
3. National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
4. Frontier Research Institute for Materials Science, Nagoya Institute of Technology, Nagoya 466-8555, Japan